Typically, an electronic/electrical device that operates using AC (Alternating Current), such as a washing machine, TV, microwave oven, dishwasher, etc., may include an apparatus that detects an over voltage or under voltage by determining whether the AC voltage supplied from an external electrical power source is higher or lower than the operating voltage for the electronic/electrical device.
In general, such an apparatus detects the over voltage or under voltage by converting the applied AC voltage to a DC voltage, and then comparing the converted voltage with a predetermined reference voltage.
However, in such a conventional apparatus, the predetermined reference voltage is the same for all electronic/electrical devices that may utilize the apparatus, regardless of the characteristics of the components that are used in each electronic/electrical device.
For example, Korean Patent Laid-Open Publication No. 2004-0046213, which was laid-open on Jun. 5, 2004, discloses technology for sensing and displaying a power error in a washing machine.